I followed the tips I outlined at the top (so far) and I am happy to report that my N810 has almost a full charge 18 hours later after I only locked it and put it in the sleeve. I didn't put it to sleep, but I did shut down chat and wireless and set my RSS feeds to manual updates. I also set my mail app (default one) to manual update too (where I have to click on refresh button). This all works out fine for me, because when I want to do these things on my N810, I am tethering to my blackberry 8800 (T-Mobile) anyway. When I am at my desktop during the day, chat and email are readily available and easier on my desktop.

The one thing that had been bugging me about my 810 was having enough of a charge when I grab it and go without leaving it plugged in all of the time.